IGFBP7 and gastric cancer: ELISA test showed that in the training cohort, the mean concentration ± standard deviation of serum IGFBP7 level in gastric cancer patients was 1.580 ± 0.198 ng/ml, which was lower than in the normal control group (1.850 ± 0.328 ng/ml, p < 0.0001, Fig. 2A).